Because a 50 50 solution of equal concentrations of acid and base neutralize each other and you will get basically a complete neutral substance like water
The heart has 2 chambers: The UPPER CHAMBERS are called the <u>atrium</u> and the LOWER CHAMBERS are called the <u>ventricles</u>
Therefore , answer is c
Answer:
The wavelength of light is 68 nm.
Explanation:
Given data:
Binding energy of electron = 176 × 10³ Kj/ mol or (1.76× 10⁶ j/mol)
Wavelength of light require to remove the electron = ?
Solution:
E = hc / λ
h = planck constant (6.63×10⁻³⁴ J/s)
c = speed of light = (3×10⁸ m/s)
The energy require per electron is
1.76 × 10⁶ j / 6.02× 10²³ = 2.92 × 10⁻¹⁸ J
Now we will put the values in formula,
E = hc / λ
λ = hc / E
λ = 6.63×10⁻³⁴ m².kg.s⁻¹ . 3×10⁸ m/s / 2.92 × 10⁻¹⁸ J
λ = 19.89×10⁻²⁶ m /2.92 × 10⁻¹⁸ (m².kg.s⁻² = J)
λ = 6.8 ×10⁻⁸ m
λ = 6.8 ×10⁻⁸ × 10⁹
λ = 68 nm
Answer:
7.37 mL of KOH
Explanation:
So here we have the following chemical formula ( already balanced ), as HNO3 reacts with KOH to form the products KNO3 and H2O. As you can tell, this is a double replacement reaction,
HNO3 + KOH → KNO3 + H2O
Step 1 : The moles of HNO3 here can be calculated through the given molar mass ( 0.140 M HNO3 ) and the mL of this nitric acid. Of course the molar mass is given by mol / L, so we would have to convert mL to L.
Mol of NHO3 = 0.140 M 30 / 1000 L = 0.140 M 0.03 L = .0042 mol
Step 2 : We can now convert the moles of HNO3 to moles of KOH through dimensional analysis,
0.0042 mol HNO2 ( 1 mol KOH / 1 mol HNO2 ) = 0.0042 mol KOH
From the formula we can see that there is 1 mole of KOH present per 1 moles of HNO2, in a 1 : 1 ratio. As expected the number of moles of each should be the same,
Step 3 : Now we can calculate the volume of KOH knowing it's moles, and molar mass ( 0.570 M ).
Volume of KOH = 0.0042 mol ( 1 L / 0.570 mol ) ( 1000 mL / 1 L ) = 7.37 mL of KOH
It’s B because of the quest